title: Expression profiling reveals MSX1 and EphB2 expression correlates with the invasion capacity of Wilms tumors.
abstract: BACKGROUND
  Wilms tumor is the most common pediatric renal malignancy, but the parameters that are important to its invasion capacity are poorly understood. The aim of this study was to identify new proteins associated with the invasion capacity of Wilms tumor.
  
  
  METHODS
  Gene expression profiles for 15 primary Wilms tumor samples were determined by Affymetrix Genechip® Human Genome Ul33A microarray analysis. The gene expression profiles for selected genes was further confirmed by quantitative RT-PCR analysis. Immunohistochemical analysis was performed on 25 Wilms tumor cases to confirm expression for Bcl2A1, EphB2, MSX1, and RIN1.
  
  
  RESULTS
  Using microarray analysis 14 genes showed differential expression (P < 0.05) comparing stage 1 non-invasive Wilms tumor to stages 2-4 invasive Wilms tumor. The differential expression for Bcl2A1, EphB2, MSX1, and RIN1 was confirmed by quantitative RT-PCR. MSX1 protein was statistically significantly lower in stages 2-4 invasive Wilms tumor cases compared to stage 1 non-invasive cases (P = 0.013). EphB2 protein was higher in stages 2-4 Wilms tumor cases compared to stage 1 cases (P = 0.006). There was no statistically significant difference between stages 1 and 2-4 Wilms tumor for Bcl2A1 (P = 0.230) or RIN1 (P = 0.969) at the protein level.
  
  
  CONCLUSIONS
  Our results indicate that MSX1 may be associated with the invasion capacity of Wilms tumors. RIN1 is a downstream effector of RAS and Bcl2A1 functions as an anti-apoptotic protein. EphB2 is an ephrin receptor and is up-regulated in invasive tumors but its role needs to be confirmed in further cases of Wilms tumors.
authors.affiliation: Children's Cancer Research Unit, The Children's Hospital at Westmead, Sydney, Australia. albertc1@chw.edu.au
authors.forename: Albert
authors.initials: A
authors.lastname: Chetcuti
authors.forename: Safiye
authors.initials: S
authors.lastname: Aktas
authors.forename: Nicole
authors.initials: N
authors.lastname: Mackie
authors.forename: Celal
authors.initials: C
authors.lastname: Ulger
authors.forename: Gokce
authors.initials: G
authors.lastname: Toruner
authors.forename: Mualla
authors.initials: M
authors.lastname: Alkan
authors.forename: Daniel
authors.initials: D
authors.lastname: Catchpoole
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007223:Infant; D051957:MSX1 Transcription Factor / Q000235:genetics*; D008297:Male; D009361:Neoplasm Invasiveness / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D036183:Receptor, EphB2 / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D009396:Wilms Tumor / Q000235:genetics* / Q000473:pathology
chemical_list: D051957:MSX1 Transcription Factor; C484083:MSX1 protein, human; D036183:Receptor, EphB2